Search results for "Signalling"

Immunohistochemical and Biomolecular Identification of Orphanin FQ, eNOS, Atrial natriuretic Factor and Oxytocin in Rat Seminal Vesicles

2009

In previous studies performed on rodents, we detected the presence of adreno-cholinergic and peptidergic innervation in seminal vesicles and other organs of the male genital system, such as prostate and ductus deferens, in which we also investigated the expression of NOS and NADPH-diaphorase. During the present project we focused our attention on the expression of some peptides involved in local control of smooth muscle relaxation, contractility, vasodilatation and control of blood flow in rat seminal vesicles. We investigated, through immunohistochemistry and RT-PCR, the presence of four peptides: orphanin, eNOS, ANF and oxytocin. Immunohistochemistry was used to detect the presence of the…

Cancer cell(s) cycle sequencing reveals universal mechanisms of apoptosis

2010

In this paper, cell cycle in higher eukaryotes and their molecular networks signals both in G 1/S and G2/M transitions are replicated in silico. Biochemical kinetics, converted into a set of differential equations, and system control theory are employed to design multi-nested digital layers to simulate protein-to-protein activation and inhibition for cell cycle dynamics in the presence of damaged genomes. Sequencing and controlling the digital process of four micro-scale species networks (p53/Mdm2/DNA damage, p21mRNA/cyclin-CDK complex, CDK/CDC25/wee1/ SKP2/APC/CKI and apoptosis target genes system) not only allows the comprehension of the mechanisms of these molecule interactions but paves…

Digital control circuitry for the p53 dynamics in cancer cell and apoptosis

2010

Experimental work and theoretical models deduce a "digital" response of the p53 transcription factor when genomic integrity is damaged. The mutual influence of p53 and its antagonist, the Mdm2 oncogene, is closed in feedback. This paper proposes an aerospace architecture for translating the p53/Mdm2/DNA damage network into a digital circuitry in which the optimal control theory is applied for obtaining the requested dynamic evolutions of some considered cell species for repairing a DNA damage. The purpose of this paper is not to improve the analysis of the actual mathematical models but to demonstrate the usefulness of such digital circuitry design to detect and predict the cell species dyn…

On p21 tracking property in cancer cell unravelled bio-digitally in silico. Are apoptosis principles universal?

2010

Upon severe DNA damage, p21 acts in a dual mode; on the one hand, it inhibits the cyclin-CDK complex for arresting the G2/M transition and on the other hand, it indirectly becomes an apoptotic factor by activating--in sequence--the retinoblastoma protein, E2F1 and APAF1 expressions. But, in a cancer cells proliferation, the mechanisms of, and participants in, the apoptosis failure remain unclear. Since the p21/p53/Mdm2 proteins network normally involves a digital response in a cancer cell, through an original design of a cell signalling-protein simulator, we demonstrate, in silico, that apoptosis phase instability is fully reciprocated by p21 mRNA irregular dynamics which operates according…

Significance of Autologous Interleukin-6 Production in the HA22T/VGH Cell Model of Hepatocellular Carcinoma

2006

Cancer cells may often support their own growth, survival, and drug resistance by autocrine/paracrine loops based on the production of different factors; results from us and others have shown that similar interleukin-6 (IL-6)-related loops are operative in multiple myeloma and prostate or renal cancer. Because this aspect has not been investigated in detail for hepatocellular carcinoma (HCC), we have examined it in HA22T/VGH cells. These differ from other primary liver cancer cell lines (that is, HepG2, HuH-6, and HuH-7) in that enzyme-linked immunosorbent assay (ELISA) showed the HA22T/VGH cells to secrete remarkable amounts of IL-6 (16.8 ng/10(6) cells/24 h); this production, due to const…

Honesty of agonistic signalling and effects of size and motivation asymmetry in contests

1999

Game theoretical models predict that the main function of fighting behaviour is to assess the relative fighting ability of opponents. The sequential assessment game has often been used to investigate contests, while honest signalling theory has received much less attention. With the wolf spider Hygrolycosa rubrofasciata we investigated whether male agonistic signalling can reveal honest information about fighting ability, and how size and motivation asymmetries affect male fighting behaviour. We also determined whether male–male competition affects the courtship behaviour of the males. We found that agonistic drumming activity is an honest indicator of male fighting ability, and that relati…

Extracellular vesicles from neural stem cells transfer the IFN-gamma/IFNGR1 complex to activate Stat1-dependent signalling in target cells

2014

TiFoSi: an efficient tool for mechanobiology simulations of epithelia

2020

[Motivation]: Emerging phenomena in developmental biology and tissue engineering are the result of feedbacks between gene expression and cell biomechanics. In that context, in silico experiments are a powerful tool to understand fundamental mechanisms and to formulate and test hypotheses.

Sympathetic neurons can produce and respond to interleukin 6

1998

Neuronal expression of cytokines is an area of active investigation in the contexts of development, disease, and normal neural function. Although cultured rat sympathetic neurons respond very weakly to exogenous interleukin 6 (IL-6), we find that addition of soluble IL-6 receptor (sIL-6R) and IL-6 enhances neuronal survival in the absence of nerve growth factor. Neutralizing monoclonal antibodies against IL-6 block these effects. Addition of IL-6 and sIL-6R also induces a subset of neuropeptide and transmitter synthetic enzyme mRNAs identical to that demonstrated for leukemia inhibitory factor, ciliary neurotrophic factor, and oncostatin M. Both of these effects are duplicated by addition o…

Chronic myeloid leukemia-derived exosomes promote tumor growth through an autocrine mechanism.

2014

Background Chronic myeloid leukemia (CML) is a clonal hematopoietic stem cell disorder in which leukemic cells display a reciprocal t(9:22) chromosomal translocation that results in the formation of the chimeric BCR-ABL oncoprotein, with a constitutive tyrosine kinase activity. Consequently, BCR-ABL causes increased proliferation, inhibition of apoptosis, and altered adhesion of leukemic blasts to the bone marrow (BM) microenvironment. It has been well documented that cancer cells can generate their own signals in order to sustain their growth and survival, and recent studies have revealed the role of cancer-derived exosomes in activating signal transduction pathways involved in cancer cell…